This invention relates to a method and apparatuss for logging earth formations of the type wherein electrical parameters and relationships of the power supply driving a transducer are recorded as the output of the transducer coupled to the earth establishes resonance conditions.
Geophysical prospecting has been used extensively for many years to obtain information about the internal structure of the earth. The usual method of doing this involves generating a pulse of energy, typically by setting off an explosive charge in a bore hole or by the operation of a mechanically driven thumper, and recording the return of the transmitted pulse as it is sent into the earth and is returned as an echo after being reflected from discontinuities. It is conventional practice to position the geophones used to receive reflected pulses or echoes in a pattern around the pulse generator. The geophone instruments typically incorporate pickup transducers to record echo pulses.